Can anyone explain me the difference between IPv4 and IPV6?

If you have completed your ccna, you would have known it. 

IPv4 is 32-bit long and IPv6 is 128-bit long, meaning IPv6 has much more ip addresses. 

format examples are 

IPv4 format: 192.168.1.1

IPv6 format: 2001:0db8:85a3:0000:0000:8a2e:0370:7334

They both are divided into private and public range based on their initial bits for example 10.0.0..0/8, 172.16.0.0/16 and 192.168.0.0/24 are the private range of IPv4 addresses.

There are more complexity associated with IPv6 addressing. But in brief these are the basic differences.